Continuing Education Activity

Coronary artery perforation is a rare complication associated with a percutaneous coronary intervention. This activity highlights the risk factors, deadly consequences, and various treatment approaches available to the interprofessional team to deal with this life-threating complication.

Objectives:

• Identify the etiology and epidemiology of coronary artery perforation.
• Review the appropriate history, physical, and evaluation of coronary artery perforation.
• Outline the treatment and management options available for coronary artery perforation.
• Discuss interprofessional team strategies for improving care coordination and communication to advance coronary artery perforation and improve outcomes.

Introduction

Coronary artery perforation (CAP) is, fortunately, a rare but serious life-threatening complication of a percutaneous coronary intervention (PCI), which in severe cases lead to cardiac tamponade, cardiogenic shock, myocardial infarction, and even death, if there is no intervention.

Etiology

Risk factors

CAP is reported to be directly proportional to the complexity of coronary artery disease.[1] Risk factors can be categorized as follows:  

A. Non-modifiable risk factors

• Old age[2]
• Female gender[2]
• History of previous coronary artery bypass graft (CABG)[3][4]
• Use of clopidogrel[5]

B. Modifiable risk factors

• Presence of hypertension [3]
• Presence of peripheral artery disease
• Presence of congestive heart failure[6]
• Lower body mass index
• Lower creatinine clearance[5]

 C. Risk factors associated with coronary anatomy and catheterization

• Complex coronary lesions (ACC/AHA Type B2, C)[7][8][9][10]
• Chronic total occlusions, heavily calcified lesions, angulated, tortuous lesions, narrow coronary arteries[7][9][10] 
• Aggressive use of oversized balloons and stents[1]
• Use of atheroablative devices and hydrophilic guidewires[1]

Epidemiology

Incidence is reported to be low and can vary between 0.1% and 3% based on the several case series with the highest risk of CAP occurring while dealing with chronic total occlusions.[2][5][7][11] Mortality rates can be as high as 21.2%, depending on the severity of CAP.[7] CAP is more common among the elderly and females, as noted above.

Pathophysiology

CAP leads to pericardial effusion, tamponade, cardiogenic shock, myocardial infarction, and even death. Hence the necessity of understanding the type and severity of perforation. Ellis classification is the most common system used in classifying CAPs. Based on the coronary angiographic findings, these are divided into three types, as follows[12]: 

Type I: Presence of extraluminal crater without extravasation

Type II: Presence of pericardial or myocardial blush without contrast jet extravasation

Type III: Presence of contrast jet extravasation through frank perforation (≥1 mm)

Type III (CS): Presence of contrast jet extravasation into the cavities like a cardiac chamber or coronary sinus

History and Physical

Most of the CAPs are recognized at the time of perforation during coronary angiography. However, subtle CAPs can go unrecognized. Acute onset of shortness of breath, hypotension, unexplained new-onset tachycardia, recurrent or persistent chest pain can develop in these later situations. CAP needs to be in the differential in these situations. As little as an accumulation of 100 ml of blood in pericardial space in the acute setting is sufficient to cause hemodynamic instability.[13] New-onset pericardial effusion on chest X-ray and a beside echocardiography post coronary intervention are diagnostic. Cardiac tamponade is associated with type B2 and C, type III CAPs, and with the use of atheroablative devices.[2][7][12][4][14][15][14][16] Delayed pericardial effusions can also be seen up to 9 days from the day of cardiac catheterization and can be challenging to diagnose. Pseudoaneurysms of coronaries can also develop at the site of CAPs. These have been reported to be as early as within 10 min from the time of PCI, with most cases between 2 weeks and 3 months.[17]

Evaluation

CAPs diagnosis is by coronary angiography. The importance of early recognition and intervention cannot be overemphasized. Serial echocardiography can be of help in diagnosing late development of pericardial effusions and tamponade, especially in patients managed with a conservative approach.

Treatment / Management

The goals of the management of CAPs are immediate hemodynamic stabilization and sealing the site of perforation to prevent dire consequences. Although there are no universally accepted treatment protocols, the following are the suggested treatment approaches:

I. General approaches: 

Adequate blood pressure support is needed. Intraaortic balloon pump may be necessary. Antiplatelets and anticoagulants need to be discontinued. Protamine infusion may be required to counteract the effect of anticoagulation. Platelet transfusion can be of some benefit, especially in those patients who have received GP-IIb/IIIa receptor antagonists. Urgent pericardiocentesis in the setting of cardiac tamponade can be life-saving. Low pressure prolonged proximal balloon inflation should take place immediately after the CAP has occurred during coronary angiography. This process is necessary to assess the severity of CAP, prevent further blood leakage, and to gain time until determining a definitive plan. 

II. Specific approaches: 

CAPs with Ellis type I and II are conservatively managed, with most cases underwent management with prolonged balloon inflation alone. [1] Serial Echocardiography after diagnosis can be helpful for timely diagnosis and management of pericardial effusions/ tamponade. 

A more severe type of CAPs (type III) treatment is via the following approaches. 

• Covered Stents (CS): The stents, initially used to treat in-stent stenosis, are used to seal the site of perforation and prevent leakage of blood. These are commonly used for proximal larger perforations. Polytetrafluoroethylene (PTFE) covered stents are widely used. Several other types of CS are also available. A study comparing the outcomes with the use of PTFE vs. polyurethane CS showed no significant differences in procedural success or major adverse cardiovascular events but showed a decrease in the rates of pericardial effusions and cardiac arrest in patients when using PTFE covered stents.[18] The disadvantages of using these stents include thrombogenicity and occlusion of coronary branches.[18] However, these demonstrate a decrease in the incidence of pericardiocentesis and the need for emergency surgeries. There are several other CS made from autologous veins and equine pericardium, but their use requires expertise and time. 

• Coils: These are made of metallic agents like stainless steel or platinum with wired structures made of PTFE or synthetic wool, which have thrombogenic properties and delivery is through guide wires or microcatheter.[18] These are commonly used for distal coronary artery perforations. The size of these coils needs to be larger than the size of the vessel involved.

• Microspheres: These are spherical, hydrophilic, and non-absorbable particles that are delivered through microcatheters to and cause precise sealing of perforations.[18] Its typical use is for distal sites of CAP similar to coils. 

• Others: Autologous blood clots suspended in contrast and saline can cause adequate sealing of CAP.[18] Thrombin injection can also help in sealing CAP by assisting in the formation of fibrin clots. Autologous subcutaneous fat also works to seal the perforation. Using blood clots and fat particles have the advantage of biocompatibility and are widely available. 

• Surgery: A cardiac surgeon needs to have involvement if cardiac tamponade is not feasible or if a pericardiocentesis does not yield appropriate results.[19] Emergency repair of CAPs or CABG in these settings also carries significant mortality risk.[14]

Differential Diagnosis

The diagnosis of CAP is usually instant during the coronary angiography. However, hemodynamic instability and persistent symptoms can be present in acute coronary syndrome, coronary artery dissection, aortic dissection, chordae tendinae rupture, and myocardial rupture.

• Acute coronary syndrome
• Coronary artery dissection
• Aortic dissection
• Chordae tendinae rupture
• Myocardial rupture

Prognosis

The prognosis of CAP depends on the severity. Ellis types I and II are conservatively managed, and most of the patients end up in spontaneous resolution or develop pseudoaneurysms. However, smaller portions develop delayed pericardial effusions and hence the necessity of serial echocardiography for the first 48 hours after diagnosing CAP. Ellis type III has a high mortality rate if ensuing cardiac tamponade is not taken care of by the above measures. 

Complications

• Cardiac tamponade
• Cardiogenic shock
• Myocardial Infarction
• Cardiac arrest
• Death

Deterrence and Patient Education

Although a rare risk, a proper explanation to the patients of this possibility during PCI before subjecting them to cardiac catheterization is necessary so that patients can give appropriately informed consent. 

Enhancing Healthcare Team Outcomes

An interprofessional team approach is necessary to deal with this dire complication. The healthcare personnel, including registered nurses, physicians, and cardiologists, should be appropriately trained to suspect any early symptoms and signs of CAP. This applies to the cardiology nursing staff and medical assistants who will monitor the patient following PCI, who can then alert the cardiac surgeon or other clinical staff immediately. This is why a cardiothoracic surgeon and anesthesiologist should be informed and readily available if the usual treatment strategies fail to contain the coronary artery perforation. WIth interprofessional effort, the rare complication can be addressed promptly and potentially save lives. [Level 5]